Catalyst-free Phospha-Nucleophilic Substitution of Hydroxylactams by Diarylphosphine Oxide

Background: A nucleophilic substitution between hydroxylactam and diarylphosphine oxide was developed for synthesizing α-aminophosphine oxide. Methods: Without a catalyst, hydroxylactams reacted with diarylphosphine oxides smoothly to furnish a series of isoindolo-β-carboline-derived phosphine oxide. Result: Isoindolo-β-carboline-derived phosphine oxides were obtained in 70-99% yields under mild reaction conditions. Notably, only water was a by-product. The mechanism of the atom-economic synthetic process was also discussed. Conclusion: The synthetic process is simple, efficiency, atom-economic and with great practical worth.